Play the slot anim or montage by left clicking on the mouse, while the animation is still playing, transition in and out the state that has the events by using "WASD" key controls to move the character.

Observe Left State Event and Fully Blended State Event don't fire

Repeat the transitions, but this time without playing the slot anim or montage, and check that all the events do indeed fire in this case

Result: Left State Event and Fully Blended State Event don't fire if there's a slot anim or montage playing

Expected: All the state specific events should fire when entering/leaving that state

Steps to Reproduce from Scratch

Create an Anim Blueprint for your character

Create a state machine for this character that contains at least 2 states

In one of the states, create the three events: Entered State Event, Left State Event and Fully Blended State Event

Place the three events in the Event Graph and connect each one to a PrintString node

In your character Blueprint, bind an input event to a PlaySlotAnimation node or a MontagePlay node

Start the game, play the slot anim or montage and, while it's still playing, transition in and out the state that has the events. Left State Event and Fully Blended State Event don't fire

Repeat the transitions, but this time without playing the slot anim or montage, and check that all the events do indeed fire in this case

Result: Left State Event and Fully Blended State Event don't fire if there's a slot anim or montage playing

Expected: All the state specific events should fire when entering/leaving that state

Have Comments or More Details?

There's no existing public thread on this issue, so head over toAnswerHub just mention UE-79507 in the post.